This invention relates generally to electric motors and, more particularly, to methods for assembling temperature sensors in electric motors.
Electric motors typically include a stationary outer portion, a stator, which surrounds an inner portion, a rotor, which rotates utilizing magnetic fields. The stator includes stator coils and stator windings, with each stator coil wound around a respective stator winding, for example U.S. Pat. No. 5,045,742. Electrical current flows through the stator coil in the respective stator winding in a time sequential manner, which generates a stator magnetic field that repels/attracts a rotor magnetic field. The electrical current flowing through the stator constantly changes in time and direction, resulting in a constantly changing stator magnetic field. Due to the changing current direction and a resulting rotating stator magnetic field of constant magnitude, the rotor is caused to rotate and generate mechanical energy.
As more electrical current is directed to the motor and increasingly changed, the rotor is caused to rotate faster. However, heat is generated by the motor due to simple resistive losses, generating counter electromagnetic forces, and hysteresis losses. If the generated heat is not adequately monitored and conducted away from the motor, the stator windings will overheat causing a breakdown of motor insulation and a permanent loss of the stator magnetic fields and the rotor magnetic field, which results in an inoperable motor.
The known methods and apparatus for monitoring temperature increase the cost and complexity of the electric motors. Further, the utilization of these known methods and apparatus lack a high degree of precision and accuracy. Due to implementation, some of these known methods and apparatus fail to accurately monitor a temperature increase in the motor.